1. What type of hours can I expect? Part time, full time? What shifts?
Our part-timers work weekends and a couple odd and end shifts during the week. Either early morning station runs or overnight routes to the hub.
2. Any idea what the starting pay rate is? I saw some old posts saying like $19/hr, but that's less than a dollar more than I make right now as a courier. Seems surprisingly low so wanted to verify.
Starting pay is location specific, so cannot help you there. Not a large disparity between courier and truck driver. You are not going to be making $5 per hour more driving a big truck.
3. How long does the CDL training take and do I start working as RTD as soon as I pass my license exam?
By the time you sign an offer letter it can take you 4-5 months before you are on the road by yourself as an RTD. Waiting for an open class and DMV test or retest if you fail can take quite a bit of your time. The RTD class here is 3 weeks by itself.